1. Field of the Art
The present invention relates generally to a boom sprayer, and more particularly to a telescoping boom sprayer having a plurality of telescoping booms carrying spray heads and moveable relative to one another. Still further, the present invention relates to a telescoping boom sprayer with spray head deactivation means to provide variable width spraying without an overlap in spraying. The invention also relates to an improved method of spraying agricultural crops and the like with a boom sprayer.
2. Description of the Prior Art
A variety of agricultural sprayers currently exist in the art. One common type of agricultural sprayer is a fixed boom or fixed length sprayer comprised of a tractor or other towing vehicle and a pair of articulated spray booms extending outwardly from opposite sides of the tractor or other towing vehicle. These booms, when extended, have a fixed length and are comprised of either single length booms or articulated boom sections which are folded in chicken wing fashion during non-use or transport. Agricultural sprayers and the like also exist which have a plurality of booms moveable relative to one another between an extended position and a retracted position.
Examples of existing spray implements include the McMahon U.S. Pat. No. 2,995,307 which discloses an articulated boom sprayer and the Nansel U.S. Pat. No. 3,055,594 which discloses an articulated, foldable boom type sprayer. The Atkinson U.S. Pat. No. 3,074,649 discloses a spraying apparatus having a single spray head at the end of a telescoping boom for spraying or washing a single element.
The High U.S. Pat. No. 2,962,307 discloses a plurality of extendable booms, with each boom having a plurality of spray heads. This patent discloses separate hoses and valves for each line of spray heads. Thus if it is desired for one spray head in a particular line to be used, all spray heads in that line must necessarily be used.
The DeWitt et al. U.S. Pat. No. 4,784,324 discloses a spraying apparatus for herbicidal and insecticidal application with an articulated and telescoping boom and with spray heads positioned on the boom.
Although many of the prior art sprayers, and in particular boom sprayers, are capable of spraying agricultural crops and the like over an extended width, they are generally incapable of spraying at lesser widths or at variable widths without a spraying overlap. Thus, to spray widths less than the maximum width of the sprayer, or to accommodate trees, posts or other obstacles that might be in the path of the sprayer booms, spraying overlap is necessary. This not only results in spraying more of the spray liquid than is needed and thereby increasing the spraying cost, but more importantly, results in double application or no application for portions of the crop being sprayed. This can lead to significantly reduced production for those areas or in some cases killing the crop as a result of over application.
Accordingly, there is a need in the art for an improved boom sprayer, and more particularly to an improved telescoping boom sprayer which is capable of spraying various widths without spray overlap.